1. Field of Invention
This invention relates to a method and apparatus for control of one or more cameras, including motion picture cameras. The invention is also related to the control of a video camera array. The invention is more particularly related to controlling parameters of a shot of a still or video camera, particularly a pan angle and zoom of the camera being controlled. The invention is also related to interfaces for implementing control of the above and other camera parameters, including pen-based, illumination, and gesture based control interfaces.
2. Discussion of Background
Video cameras with controllable pan/zoom are commercially available. For example, SONY EVI-D30 has a range of zoom, tilt and pan that is controllable. Deep Sea Power & Light also produces a camera (the Pan/Tilt/Zoom 2001) having controllable pan tilt and zoom (specifically designed for underwater operation). However, such systems are constrained by the limitations of the mechanical systems that orient them.
Current interfaces to movable and cameras are not particularly intuitive, and typically consist of contact switches that move the camera up/down, left/right, and control a degree of zooming. Often, users must “pre-program various functions”. For example, the SONY EVI-D30 requires a user to “pre-define” a subject for tracking, or alternatively to control the camera via an RS-232 interface.
Typically, motion of a movable camera is at one slow speed, to avoid overshoot, even if the control motors are capable of variable speeds. Even professional systems have only a joystick, which limits the interface from instantaneously panning to a new destination even if the camera control hardware supports it. For example, the DEEPSEA Power & Light Pan/Tilt/Zoom 2001 requires switching of control lines to either 12VDC or 12Vret for camera control, and has a joystick control option.
A particular advantage of virtual cameras is that they can be panned/zoomed virtually instantaneously, with none of the speed limitations due to moving a physical camera and/or lens. For example, Foote et al., Ser. No. 09/370,406, filed Aug. 9, 1999, incorporated herein by reference, in its entirety, discloses several embodiments of virtual cameras constructed from both fixed and movable cameras and camera arrays.